Add new row to DataGridView error: the program cannot commit or quit a cell value change

Question

I'm writing this application in C#, .NET 4, winforms.

I want to programatically add new row to a datagridview which is bound to a collection. When I do that I get an exception. (note: when user creates new row via datagridview (types something into new row) I have no problems).

locationBindingSource.AddNew(); //this is bound to datagridview
var row = locationsDGV.Rows[locationsDGV.Rows.Count - 2]; //get the new row
locationsDGV.CurrentCell = row.Cells[0]; //switch to new row <-throws error

Error that is thrown: System.InvalidOperationException was unhandled. Operation did not succeed because the program cannot commit or quit a cell value change.

I need to switch to a new row to ensure that user won't leave row in not validated state.

Is it possible to overcome this without disabling row validation?

Thank you for you answers.

EDIT: Bindingsource is populated with objects created by Entity Framework. When a user creates a new object, for instance "location", it is created with default values, which can't be saved to database, thus I need validation. I validate that all important fields are not empty (or filled with default values). If they are I cancel validation. I think you can easily recreate it with just a simple bindinglist of simple(one string field should be enough) objects bound to a datagridview. Then create a row validating event and validate using something similar.

Location location = (Location)locationBindingSource.Current;
if (string.isNullOrWhitespace(location.stringProperty))
    e.cancel=true;

Maybe a better approach would be to add your row to the DataGridView instead of the datasource and include default data that is not invalid. Similar to this: Add new row to DataGridView — Brad Rem
If possible can you give enough code in your question to duplicate the issue - in particular that code you use to populate the bindingsource and any code that is triggered on validation. — David Hall
I've managed to duplicate the error (adding in some validaiton code) but you might want to include your actual code in case other people can help. I'm still looking. — David Hall

gps gps · Accepted Answer · 2014-07-23T21:09:11

It looks like you need to validate the event. See this thread: http://social.msdn.microsoft.com/Forums/windows/en-US/91883e42-68eb-40b9-9eae-3b76f671a48b/operation-did-not-succeed-because-the-program-cannot-commit-or-quit-a-cell-value-change?forum=winformsdatacontrols.

Here's more detailed documentation on the CellValidation event: http://msdn.microsoft.com/en-us/library/system.windows.forms.datagridview.cellvalidating.aspx

Add new row to DataGridView error: the program cannot commit or quit a cell value change

1 Answers